Caudal epidural steroid treatment is when a corticosteroid drug is injected into the epidural space (in your back), usually as a treatment for nerve root pain (sciatica). The injection is given lower down on your back, through an opening in the sacral bone (caudal epidural). Caudal epidurals are usually carried out under local anaesthetic (when you are awake). The skin is cleaned with antiseptic and the bottom opening into the spine (opening in thesacral bone) is injected with the therapeutic mix of drugs.